1.Technical Field
The present disclosure relates to orthopedic devices and, more particularly, to bone implantation and stabilization assemblies, and devices for deploying and/or undeploying such bone implantation and stabilization assemblies.
2.Background Art
In general, bone implantation and stabilization assemblies (e.g., pedicle or bone screw or anchor assemblies) and the like are known in the art and may be used for connecting vertebrae or other spinal or bone structure to rods or the like during surgery (e.g., spinal surgery). For example, U.S. Pat. No. 5,443,467 to Biedermann incorporates a ball joint at the connection to the rod to allow the surgeon some flexibility in placing the screws. Tightening a nut on the screw compresses the ball joint components to lock the angular position of the ball joint.
Some typical bone implantation and stabilization assemblies (e.g., bone screw or anchor assemblies) generally include a screw member or anchoring element (e.g., pedicle screw) having a threaded portion and a head, the head generally having a spherically shaped portion, the assembly also typically having a cylindrical-like receiver member for receiving the head of the screw member and a rod (e.g., stabilization rod). However, no bone implantation and stabilization assembly design is free of problems and there is still a need for an assembly that is user-friendly suiting all kinds of bone conditions and which permits improved implantation and/or stabilization of the assembly (e.g., improved implantation and/or stabilization of the bone screw or bone anchoring element), and/or which permits improved deployment and/or undeployment of the assembly.
As another example, fractures of limb bones have been treated with internal fixation or stabilization devices, such as nails running inside the medullary canal of a fractured bone, plates lying on the surface of a bone, and/or screws affixing both ends of a fractured bone together. In general, an intramedullary fixation method is a traditional procedure for treating long bone fractures. Such methods typically involve affixing the bone fracture using intramedullary nails, without disturbing the periosteum of the bone. Some disadvantages associated with conventional intramedullary fixation methods include lack of rotation stability (e.g., fractured bone segments connected by a nail can rotate relative to each other), lack of longitudinal stability (e.g., fractured bone segments connected by a nail can move relative to each other along an axis of the nail), collapse of the fracture site in some fracture types, and/or undesired backup of nails. Additionally, some intramedullary fixation methods may introduce interlocking screws across the nail, creating some disadvantages.
For example, conventional intramedullary fixation nails for long bones may include a rigid structure that may be locked at their end portions by the addition of screws transversally applied through the bone walls and the nail itself. In general, this additional step typically increases the duration and/or complexity of the operation, and may require additional skin incisions and/or longer use of an image intensifier (e.g., X-ray). Moreover, undesired gaps between the bone ends may originate from the screws, which are permanent unless removed in a new operation. In addition, metallic intramedullary nails may propagate contamination through the entire canal, despite attempts at cleaning the fracture site, which may lead to bone infection. While increased stability in an intramedullary fixation device may be desirable, it may also be desired in some situations to remove or change the stabilization or fixation device (e.g., in the event of infection or non-union). However, in such scenarios, the stabilization or fixation device may be difficult to remove without significantly damaging bone tissue.
Thus, despite efforts to date, a need remains for advantageous and efficient systems/methods that provide for improved bone implantation and stabilization assemblies, and improved systems/methods for deploying and/or undeploying such advantageous bone implantation and stabilization assemblies. These and other inefficiencies and opportunities for improvement are addressed and/or overcome by the systems/methods of the present disclosure.